Artificial leg.



V. LAZZARA.

ARTIFICIAL LEG. V APPLOATION FILED AUG. e. 1912.

Patented Nov. 19, 1912.

' lJeli'ersonstreet, gin the borough of Brooklyn, y,5111"fthe Cltyof New York, oountyof Kings,

, l.and State of NewYork, have invented cer- `tain newand useful Improvements in rtr `specification.

ficial Legs, of which the following` is a This invention relates to improvements in Aartificial legs audits prin'iary object is to devisek improved means for automatically locking the leg` at the knee when straightened, the said means, being manually releasable when it is desired to bend the leg.

The various other lobjects of the luren tion will be more fully set forth in the fcllowing description of one form of mechanisni embodying the invention which consists in the new and novel feature of construction and combination of parts hereinafter set forth and claimed.

Referring to the accompanying draw ings :wFigure l is a side elevation of the leg when bent at the, knee showing the outer side-thereof. Fig. 2 is a fragmental view of Fig. l. showing the leg straightened, and 'Fig'. 3 is a vertical central sectional view at right angles to Fig. 2.

My embodimentl is preferably shown in connection with an artificial leg formed of leather, raw-hide, or a similar substance, and comprises an upper part a, a lower part b, and a foot- 0. Such material is especially adapted for artificial legs on account of its comparative strength and lightness, and the facility with which it may be formed and cut to suitable shapes at the joints. The lower leg part b, is strengthened at each side by the bars Ze-Z conveniently secured to the leg by bolts e. The bars are suitably curved at their lower ends for pivotally connect-ing them to the foot c, as vby means of the screws f.

Plates g and 71, are preferably secured to the upper ends of the bars (Z by, bolt a, but they may be formed integrally with the bars if desired. These-plates are extended upwardly beyond the bars, and are further se..a cured to the lower leg part by bolts ,7.

` Strengthening plates 7s are secured to the interior of the lower leg part, by means of the bolts z' and thereby strengthening the ljoint between the plates g and 7i and their TENTFF r respective bars d. The plates g and andl the upper endof thelower leg part are fur- I "aminorar, neel 'i y A. Y i vlf'Spiecllcablon of Letters Patentz i" APt-(J`,lriiill NGV-l l vIApplication lecl August 6. i i .i A.

1912. .serial ne, 713.566,- i y ther strengthened by an adjustable boltZ.

This bolt is tapped at one end into the plate L and passes freely at its other end through thejplate g. This end is threaded to receive the bolts v11i-m. By properly adjustv ingthese bolts the lower leg part inni' be made' to snugly fit the upper part ofthe leg: The bolt Z also serves to stillen bothpar'ts of the leg. Plates new() are secured to theupper leg part o by screws p and the upper ends are preferably secured in .leather sheathsg. The plates fn, and o overlap `the plates g and. 71, respectively and are piro-tally connected to lhein by the bolts r. Theplate g, which is the plate on the outer side of the leg is disposed on the outside of the plate 71.. 'l his plate has formed upon its rear side a rounding cam s, which terminates atthe top in a notch t having` a stop u on the farther side of it. A latch o is slidably mounted in sleeves /w secured on t-he plate n. The lower end of this latch is adapted to set in the notch f; and to slide upon the cam s when lifted from the notch, as when the lower leg part is turned about its pivotal, connection. The .latch is formed with a linger piece c for raising` it., and hes a spring g/ mounted upon it between the upper sleeve w and a pin ,e set in the latch. rlhis spring holds the latch upon the cam and causes it to snap into the notch when the leg is turned 'to bring the latch and notch into alinenient..

A knee piece a avis secured to the lower end of the upper leg,r part. This is preferably made of leather in the form of a hollow shell, and is of sufficient length to dip or extend into the hollow interior of the lower leg part when the parts are bent as shown in Fig. l. lt has enough resiliency to set firmly, but yieldingly, against the upper edge of the lower leg:T part b. Vhen the leg is straightened as shown in Fig. 2, the knee turns into vthe hollow interior or the lower leg part beneath the bolt Z.

ln operating` the leg, all that the wearer asshow'hvln Fig. 1.l When the wearer rises,

the 4legjstraightens automatically and the ,latch follows the cam and when it reaches the noteht-it snaps into place. The stop -u- @serves to prevent' the latch from passing to the otherside of the notch.

if. Although I have shown only one forni of mechanism'embodying my invention, it is obvious that various rchanges within the skill of the vmechanic may be made therein without' departing from the spirit of the inYenlt-ion, provided the means set forth in the .following claims are employed.

Y'Having thus described my invention,` I claim' ljfln an artificial leg, an upper part, a

flot-wer part,'a plate secured t0 the upper part ont-he outer side thereof, a plate secured tothe lower part on the outerside thereof,

automatically' lowering it, a Cain formed on th-top of the lower plat-e having a notch at the forward endfor receiving the latch t0 lock the leg in straightened position, said cam being adapted to hold'the latch bolt back in setposition when disengaged from the notch, and an extension on the-forward end of said earn for stopping the latch bolt when brought to register with said notch.

2. In an artificial leg, an upper part and a lower part made hollow of sheets of leather, plates of metal reinforcing the said .parts at bothsides and pivotally connected to form the .knee joint, a reinforcing bolt tapped into one of the platesand extending through the corresponding leg part and loosely through the opposite plate, and nuts screwed on said bolt each side of said last plate affording adjusting means for the transverse dimensions of said leg parts.

' This specification, signed and witnessed this 26th dag7 of July, A. D. 1912.'

VINCENZO LAZZARA. Vitnesses': i A

SAX-Emo CORREALEY, VICTOR LIoTA. 

